This blog will list news about all aspects of scorpion biology and important taxonomical updates from The scorpion Files. The Scorpion Files is a leading information source about scorpions, and has among others an updated list of all extant families, genera and species.(C) Jan Ove Rein and The Scorpion Files.

01 October, 2015

Brachistosternus Pocock, 1893 (Bothriuridae) is a very abundant taxa in most arid to semi-arid habitats of southern and western South America. Andres Ojanguren-Affilastro and co-workers have recently published the first phylogenetic analysis of Brachistosternus based on molecular and morphological data.

See abstract and article for further details.

Abstract:A phylogenetic analysis of the scorpion genus Brachistosternus
Pocock, 1893 (Bothriuridae Simon, 1880) is presented, based on a dataset
including 41 of the 43 described species and five outgroups, 116
morphological characters and more than 4150 base-pairs of DNA sequence
from the nuclear 18S rDNA and 28S rDNA gene loci, and the mitochondrial
12S rDNA, 16S rDNA, and Cytochrome c Oxidase Subunit I gene loci.
Analyses conducted using parsimony, Maximum Likelihood and Bayesian
Inference were largely congruent with high support for most clades. The
results confirmed the monophyly of Brachistosternus, the nominal subgenus, and subgenus Ministernus
Francke, 1985, as in previous analyses based only on morphology, but
differed in several other respects. Species from the plains of the
Atacama Desert diverged basally whereas the high altitude Andean species
radiated from a more derived ancestor, presumably as a consequence of Andean uplift and associated changes in climate. Species limits were
assessed among species that contain intraspecific variation (e.g.,
different morphs), are difficult to separate morphologically, and/or
exhibit widespread or disjunct distributions. The extent of convergence
in morphological adaptation to life on sandy substrata (psammophily) and
the complexity of the male genitalia, or hemispermatophores, was
investigated. Psammophily evolved on at least four independent
occasions. The lobe regions of the hemispermatophore increased in
complexity on three independent occasions, and decreased in complexity
on another three independent occasions.